The trick to time management is to realize that there is not enough time. There never is. Time is the most precious and fleeting resource.
Don’t procrastinate. Do now what you can. The future is more uncertain, something may come up (and usually does) to alter your plans. Early work also allows you to come back to it and review it later.
Build in some slack time for wriggle room. One of my favorite supervisors told me to not schedule the entire work week. He wanted me to have some minimum free time to accommodate last minute requests from him. I try to maintain that philosophy. I don’t allow that unscheduled time to go to waste, instead I use it for things like professional development like reading up on industry newsletters or reaching out to others in the field.
Include transitional times and account for set up. An hour for dinner may or may not be an hour of eating. There’s cooking, eating and cleaning dishes. There’s shopping for ingredients or the drive to a restaurant.
Keep a schedule like a financial budget–have something aspirational, review and adapt.